This invention relates to diaphragm pumps and more particularly to such pumps for use with corrosive fluids.
A major drawback of many popular industrial pumps, i.e., piston, impeller or the like is that such pumps employ relatively movable seals and bearings in a compressive means in an attempt to protect and/or separate the pump drive means from the fluid handled by the pump. Not only must such seals and bearings be routinely repaired or replaced due to normal wear and tear thereof, these components often exhibit accelerated wear and failure where the pump is required to handle corrosive fluids.
Diaphragm pumps have been employed in industrial applications for use with chemically aggressive and/or corrosive fluids with limited success. While such pumps employ as pumping members diaphragms fixedly sealed about the perimeter thereof, therefor requiring no movable seals or bearings, various other of the pump components being formed from conventional materials subject to premature failure from attack by corrosive fluids render such prior art diaphragm pumps not entirely suitable for use with corrosive fluids.
Although certain relatively inert materials such as polypropylene and polytetrafluoroethylene are known to be able to withstand exposure to many corrosive industrial fluids, the strength of such materials has heretofore limited their use in industrial pumps to linings for the various wetted pump components. Thus, diaphragm pumps such as that disclosed in U.S. Pat. No. 3,000,320 to Ring for handling corrosive fluids are required to have all the wetted components thereof formed from structural material such as steel and the like lined with a suitable chemically inert material as by coating, molding or laminating techniques.
Accordingly, it is a principal object of the present invention to provide a diaphragm pump which overcomes the deficiencies of the prior art.
It is another object of the present invention to provide a diaphragm pump capable of handling corrosive fluids without risk of corrosive attack of the pump by the fluid.
It is another object of the present invention to provide a diaphragm pump for handling corrosive fluids wherein the pump is formed entirely from chemically inert materials.
It is yet another object of the present invention to provide a diaphragm pump for handling corrosive fluids, the pump being economic to manufacture .